#!/usr/bin/env python
#coding=utf-8
import time

start = time.time()
def gcd(m,n):
    if m<n:
        m,n = n,m
    while True:
        m,n = n,m%n
        if n == 0:
            return m
result = 2
def lcd(m,n):
    return m*n/gcd(m,n)
for i in xrange(3,21):
    result = lcd(i,result)
print result
print time.time() - start

